This present study aimed to determine the efficacy of supplementing layer diets with vitamin A(0, 8,000 and16,000 IU/kg diet) and vitamin E(0, 250 and 500 mg/kg diet) either individually or in combination on egg produ...This present study aimed to determine the efficacy of supplementing layer diets with vitamin A(0, 8,000 and16,000 IU/kg diet) and vitamin E(0, 250 and 500 mg/kg diet) either individually or in combination on egg production and quality, and blood hematology and chemistry of birds reared under summer conditions. A total of 135 Bovans Brown laying hens were distributed to 9 treatment groups with 5 replicates of 3 hens/pen in a 3 × 3 factorial design. A significant improvement in feed conversion ratio(FCR) was observed as supplementary vitamin A or E increased(P 0.01). Hens fed diets supplemented with 16,000 IU vitamin A plus 500 mg vitamin E/kg diet had the best FCR among all groups. Egg quality traits were not significantly affected by the interaction of vitamin A and vitamin E levels. There was a significant increase in monocytes(P ≤ 0.01)and a decrease in basophils counts(P ≤ 0.05) in response to vitamin E. Significant decreases were observed in packed cell volume(PCV), thyroxine(T_4), alanine transferase(ALT), albumin, total cholesterol and total lipids((P ≤ 0.05 or P ≤ 0.01) P 0.01), and increases were observed in serum concentrations of globulin(P ≤ 0.05)and calcium(P ≤ 0.01) due to vitamin A. The combination of 0 IU vitamin A and 500 mg vitamin E/kg diet had the highest values of PCV(40.09%) and hemoglobin(Hb)(10.33 mg/100 mL) among all groups. Vitamin E raised serum values of total protein, total cholesterol and total lipids(P ≤ 0.05 or P≤ 0.01). Feed intake, FCR,PCV, Hb, lymphocytes, monocytes, eosinophils, T_4, ALT and total protein were significantly affected by the interaction of vitamins A and E(P ≤ 0.05 or P ≤ 0.01). The interaction of vitamins A and E was only significant with respect to serum total protein(P ≤ 0.05). It can be concluded that layer diets supplemented with vitamins A and E had good results in alleviating the harmful impacts of high ambient temperature. The combination of 16,000 IU vitamin A and 500 mg vitamin E per kilogram diet is preferable for obtaining better production of laying hens reared under hot summer conditions.展开更多
文摘This present study aimed to determine the efficacy of supplementing layer diets with vitamin A(0, 8,000 and16,000 IU/kg diet) and vitamin E(0, 250 and 500 mg/kg diet) either individually or in combination on egg production and quality, and blood hematology and chemistry of birds reared under summer conditions. A total of 135 Bovans Brown laying hens were distributed to 9 treatment groups with 5 replicates of 3 hens/pen in a 3 × 3 factorial design. A significant improvement in feed conversion ratio(FCR) was observed as supplementary vitamin A or E increased(P 0.01). Hens fed diets supplemented with 16,000 IU vitamin A plus 500 mg vitamin E/kg diet had the best FCR among all groups. Egg quality traits were not significantly affected by the interaction of vitamin A and vitamin E levels. There was a significant increase in monocytes(P ≤ 0.01)and a decrease in basophils counts(P ≤ 0.05) in response to vitamin E. Significant decreases were observed in packed cell volume(PCV), thyroxine(T_4), alanine transferase(ALT), albumin, total cholesterol and total lipids((P ≤ 0.05 or P ≤ 0.01) P 0.01), and increases were observed in serum concentrations of globulin(P ≤ 0.05)and calcium(P ≤ 0.01) due to vitamin A. The combination of 0 IU vitamin A and 500 mg vitamin E/kg diet had the highest values of PCV(40.09%) and hemoglobin(Hb)(10.33 mg/100 mL) among all groups. Vitamin E raised serum values of total protein, total cholesterol and total lipids(P ≤ 0.05 or P≤ 0.01). Feed intake, FCR,PCV, Hb, lymphocytes, monocytes, eosinophils, T_4, ALT and total protein were significantly affected by the interaction of vitamins A and E(P ≤ 0.05 or P ≤ 0.01). The interaction of vitamins A and E was only significant with respect to serum total protein(P ≤ 0.05). It can be concluded that layer diets supplemented with vitamins A and E had good results in alleviating the harmful impacts of high ambient temperature. The combination of 16,000 IU vitamin A and 500 mg vitamin E per kilogram diet is preferable for obtaining better production of laying hens reared under hot summer conditions.
